<!DOCTYPE html>
<html>
  <head>
    <title>Frame with WebView</title>
    <style>
      body {
        margin: 0;
        padding: 0;
      }
      webview {
        position: absolute;
        left: 100px;
        top: 200px;
        width: 200px;
        height: 100px;
        outline: 1px solid #000;
      }
    </style>
  </head>
  <body>
    <button>Outer</button>
    <webview src="data:text/html,<body style='margin: 0; padding: 0;'><button>Inner</button>"></webview>
  </body>
</html>
